Something is shorting making that code come up. It's obviously NOT the ECM. Check out these two links and do some more research. Of particular interest is post #3 of this first link below. It's about a Chevy, but you may be interested since it's a similar situation. Here's a quote from post #3:
I ran into a Chevrolet a couple weeks ago with similar symptoms (intermittent loss of acceleration, check engine light) and it ended up being a 5v reference wire shorting to the camshaft position sensor's signal wire. It's entire harness was melted causing intermittent shorting. This was killing one of the 5v reference circuits in the computer. It was setting the P0606 code, as well as another code for loss of 5v reference "B", and a few other codes as well. It ended up not needing a computer.
The whole thread is here:
https://www.toyotanation.com/forum/...54-p0606-check-engine-light-2005-corolla.html
Here's another thread that gives another idea:
https://www.iatn.net/forums/13/55176/toyota-p0606-dont-replace-the-ecm
Good luck and let us know what you find out.
I ran into a Chevrolet a couple weeks ago with similar symptoms (intermittent loss of acceleration, check engine light) and it ended up being a 5v reference wire shorting to the camshaft position sensor's signal wire. It's entire harness was melted causing intermittent shorting. This was killing one of the 5v reference circuits in the computer. It was setting the P0606 code, as well as another code for loss of 5v reference "B", and a few other codes as well. It ended up not needing a computer.
The whole thread is here:
https://www.toyotanation.com/forum/...54-p0606-check-engine-light-2005-corolla.html
Here's another thread that gives another idea:
https://www.iatn.net/forums/13/55176/toyota-p0606-dont-replace-the-ecm
Good luck and let us know what you find out.